The Naveta d'Es Tudons is the most remarkable megalithic chamber tomb in the Balearic island of Menorca.
In Menorca and Majorca there are several dozen habitational and funerary naveta complexes, some of which similarly comprise two storeys. Navetas are chronologically pre-Talaiotic constructions.
The Naveta d'Es Tudons served as collective ossuary between 1200 and 750 BC. The lower chamber was for stashing the disarticulated bones of the dead after the flesh had been removed while the upper chamber was probably used for the drying of recently placed corpses. Radiocarbon dating of the bones found in the different funerary navetas in Menorca indicate a usage period between about 1130-820 BC, but the navetas like the Naveta d'Es Tudons are probably older.
The shape of the Naveta d'Es Tudons is that of a boat upside down, with the stern as its trapezoidal façade and the bow as its rounded apse. Its groundplan is an elongated semicircle. Externally, the edifice is 14.5 m long by 6.5 m wide and 4.55 m high but it would originally have been 6 m high.
The front, side walls and apse of the edifice consist of successive horizontal corbelled courses of huge rectangular or square limestone blocks dressed with a hammer and fitted together without mortar, with an all-round foundation course of blocks of even greater size laid on edge.
The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.